Cookie policy
Updated November 9, 2026.
The short version
We don't set any cookies of our own, and we don't run analytics. The site keeps a few notes in your own browser so it can remember the calculators you use, and our host may set a security cookie to stop attacks. We show ads from Google: Google and its partners use cookies that can personalize ads based on your visits to this and other sites, and Google asks for your consent first where the law requires it.
What cookies and local storage are
A cookie is a small text file a website saves in your browser and reads back on later visits. Local storage does a similar job but stays on your device: the website's code can read it, but your browser doesn't send it with each request. We use local storage for our own features, so nothing about the calculators you use leaves your device.
What this site stores
Our own notes, in your browser's local storage
sc:saved: the calculators you saved with the star, shown on the home page.sc:recent: the calculators you used recently, shown on the home page.sc:vfollowed by a page address: remembers that you answered "Was this helpful?" on that page, so each browser votes once.
How long: until you clear them. They're never sent to us.
Security cookies from Cloudflare, our host
__cf_bm and cf_clearance are strictly necessary cookies, set only when bot protection or a security check is in use, to tell people from harmful automated traffic. How long: __cf_bm expires 30 minutes after your last request; cf_clearance lasts for a limited time set in the site's security settings. Cloudflare explains them in Cloudflare cookies.
Advertising cookies from Google
Google and its partners use cookies to show ads, limit how often you see the same one, measure them and, if you agree, make them personal. How long: it varies by cookie; Google lists each one in how Google uses cookies.
Your choices
- Advertising cookies: in the UK, the European Economic Area and Switzerland, Google's consent tool asks before setting them, and its link on the page lets you change your mind. In US states with privacy laws, the same tool lets you opt out of your information being sold or shared. Anywhere, you can turn off personalized ads in Google's Ads Settings.
- Our local storage: clear this site's data in your browser settings to delete your saved and recent calculators. The site still works; it just won't remember them.
- Blocking cookies: your browser can block or delete cookies. The calculators keep working, though a security check may appear more often.
Questions
Email [email protected]. The privacy policy explains what data the site handles and your rights.